Air-preheating device



Dec. 17, 1929. v 0. DE LORENZ] 1,739,507

AIR PREHEATING DEVICE Filed Dec. 1925 3 Sheets-Sheet 1 Dec. 17, 1929. 0. DE LORENZ] 1,739,507

AIR PREHEATING DEVICE Filed Dec. 9. 1925 s Shets-Sheet 2 zzwfw 3 Sheets-Sheet 3 0. DE LORENZ] AIR PREHEA'I ING DEVICE Filed Dec Dec. 17, 1929.

Patented Dec. 17, 1929 UNITED STATES PATENT OFFICE o'r'ro DE LonENzI, or MAPLEWOOD, NEW JERSEY, asarenon '10 INTERNATIONAL COMBUSTION ENGINEERING CORPORATION, 0E NEw 'YoBx, N. Y., aconronA'rIoN 0E DELAWARE Application filed December This invention relates to air preheaters and is especially useful for combustion 'chambers burning pulverized fuel and provided with boiler surfaces subject to radiant heat, where a high degree of preheat of the combustion air is required to increase the fur- *with the description of the invention.

How the foregoing together with such other objects and advantages as may hereinafter appear or are incident to my invention, are realized, is illustrated in preferred form in the accompanying drawings, wherein:

Fig. 1 is a longitudinal sectional view thru the heater taken on the line 1-1 of Fig. 2;

Fig.2is a transverse sectional view thru the heater taken on ti 1e line 22 of Fig. 1

Fig. 3: is a plan section taken on the line 3-3 of Fig. 1;

Fig. 4 is an enlarged fragmentary detailed section of the regenerative elements taken on the line 4.4 of Fig. 3; and

. Fig. 5 is a section taken on the line 5-5 of Fig. 4;.

Referring to the drawings the reference character A denotes the casing of the air heater said casing comprising an upper portion 7, a lower portion 8 and a main or intermediate portion 9. The upper portion 7 is divided into two compartments 10 and 11 by the partition 12 and the lower portion is divided into two compartments 13 and 14 by the partition 15, said compartments extending crosswise of the heater. The main or intermediate portion 9 of the casing A contains the regenerative elements indicated as a whole by the reference character B said elements comprising AIR-PREHEATING DEVICE 9, 1925. Serial N6. 74,426.

a plurality of alternate flat and corrugated plates 16 and 17 respectively held in closely stacked relation as for instance by means of the buckstays 18, spacers 19 and tie rods 20 although any other suitable means of holding them stacked may be employed.

It will be seen that by so constructing the regenerative elements a multiplicity of rows of narrow vertical passages are formed each vertical passage being subdivided into a plurality of smaller passages by virtue of the corrugations. Hence a large quantity of heating surface is afforded in a relatively small heater.

It is to be noted that the flat plates 16 extend for substantially the full height of the main portion 9. of the casing while the corrugated plates 17 are interrupted adjacent their upper and lower edges thus providing the equalizing spaces or chambers 21 and 22 for equally distributing the air or waste gas, as the case may be, through the regen erative elements.

A waste gas duct 23 leads the waste gases of combustion from the associated furnace (not shown) to one of the lowercompartments previously mentioned in this instance the compartment 14 and a similar duct 24 is provided for leading ofl said gases from'the opposite upper compartment 10 after having passed thru certain of the heater passages.-

ber of the furnace thru the medium of the duct 26, thus providing the preheated combustion air for the furnace.

Directly above and below the regenerative elements B I have provided the movable grid like members 27 and 28 for controlling the passage of the air and waste gases thru the heater. It will be noted thatthese members 27 and-28 are, each provided with two sets of spaced transverse openings 29, the set of openings in one half being staggered with relation to the set in the other half. It is further pointed out in this connection that the openings in the upper member 27 are so disposed with relation to the openings in the lower member; 28 that they do not align in assembly, this bein clearly shown in the drawings particular y in Fig. 3.

The grid-like members 27 and 28 are each provided with a plurality of equally spaced yielding seals 30 on their faces adjacent the regenerative elements which seals extend across the width of the heater to form a plurality of transverse chambers 31, one for each opening 29, in the members 27 and 28.

Assuming now that air is admitted in a downward direction to the compartment 11 it will pass thru all of the openings 29 which communicate with said compartment, enter their chambers 31 therebelow, pass down thru the corrugationsin the regenerative elements included between seals defining said chambers, enter the equalizing chamber 21, pass thru the regenerative elements,

. lower equalizing chamber 22, pass thru the versa.

openings 29 in the opposite half ofthe lower grid-like member 28 and finally pass-to thefurnace thru the medium of the duct 26.

The waste gases are passed thru the heater in an upward direction in a manner very similar to the downward passing of the air, said gas however passing thru the passages adjacent the ones thru which air is being passed. Thus it will be seen that a plurality of alternate groups of gas and air pas sages are provided. The gas in passing thru the heater gives oif heat to the regenerative elements an the air in passing thru the heater absorbs the heat of the previously heated-elements. In order to maintain a substantially uniform degree of reheat I have. provided means for oscillating the grid-like members 27 and 28 whereby to continually transform the gas passages to air passages and vice This I accomplish by means of the motor device 32 adapted to drive the cranks 33, 33 which in turn. are connected to the members 27 and 28 by the links 34 and 35 respectively there bein provision made for lost motion by virtue o the slots in the links 34 and 35.

Thus it will be seen that during approxi-' mately one quarter of the stroke of the cranks the grids are moved rather quickly to uncover heated elements to incoming air and remain in such position for .the next quarter stroke and so on.

Thus highly heated regenerative elements are transformed-to air passages and cooled elements are transformed to waste heat passages whereby the degree of preheat is maintained substantially constant, for obviously by this arrangement no group of elements is kept in service, as a group, long enough for all the elements thereof to become cooled.

It is pointed out that due to this continual transformation of gas and air passages the heater will be much less subject to dirt than other types of heaters and need only be cleaned occasionally.

By the use of alternate flat and-corrugated plates itwill be seen that a large amount of eating surface is provided whereby-I am enabled to greatly reduce thesize of .the heater for a given amount of preheat and am enabled to obtain a degree of preheat which it would be impossible tov obtain in a heater of the indirect type without going to sizes which would be prohibitive from a practical standpoint.

I claim I 1. A waste gas air heater of the regenerative type including a-casing connected to a source of waste gas and 'also to a source of air, metallic regendrative elements dividing the interior into a multiplicity of passages, a laterally movable element above said regenen r t e erative'elements, a laterally movable element therebelow, a plurality of members carried by each of said movable elements adapted to contact with the regenerative elements and spaced to include several thereof, each of said 'movable elements including a member having two sets of spaced openings therein, one set of openings beingstaggered with respect to the other set of openings in the same element, and the openings .in one element being staggered with respect to the openings'fin the other element, one set of openings in each element, communicating with a waste gas pas sage and the other set communicating with" an air passage, said movable elements when moved transforming heated regenerat1veelements to air-passages and cooled regenerative elements to gas passages. w

. 2. A waste gas air heater ofgthe regenerative type including a casing ha ing its lower and upper portions divided into two compartments, and having a plurality of regenerative elements within its main or.intermediate portion; a conduit for introducing waste gases to one of the lower compartments and a conduit for leadingofl' the waste gases from one oi the upper compartments; a conduit for introducing air to the other upper compartment and a conduit for leading ofi the air from the other lower compartment, a

movable element between the upper portion of the casing and the regenerative elements and a movable element: between the lower portion of the casing and the regenerative elements, each of said movable elements including a member having two sets of spaced easing into alternate gas and air passages and when moved to transform the gas passages to air passages and vice versa.

3. A waste gas air heater of the regenerative type including a casing the interior of which is divided into a multiplicity of vertical passages by alternate flat and corrugated regenerative elements, a waste gas conduit and an air conduit leading to the said passages and similar conduits leading from said passages, grid members covering said passages, each having two sets of spaced openings therein, one set of openings being staggered with respect to the other set and the openings in one grid being staggered with respect to the openings .in the other grid, one set of openings in each grid communicating with the waste gas conduit and the other set communicating with the air conduit, said grid being movable to alternately admit gas and air to said passages.

4. A waste gas air heater of the regenerative type including a casing the interior of which is divided into a multiplicity of vertical passages by alternate flat and corrugated regenerative elements, a waste gas conduit and an air conduit leading to the said passages and similar conduits leading from said passages, grid members covering said passages, each having two sets ofv spaced openings therein, one set of o nings belng staggered with respect to the other set and-the openings in one grid being staggered with respect to the openings in the other grid, one

set of openings in each grid communicating with the waste gas conduit and the other set communicating with the air conduit, said grids being movable to alternately admit gas and air to said passages togetherwith means associated with said regenerative elements to equally distribute the gas and air through the aforesaid vertical passages.

5. A regenerative preheater for air and the like in furnace plants, comprising a casing divided transversely into a plurality of 'open compartments, and a regenerative mass of heat interchanging members located within said compartments; a pair of distributin hoods located respectively upon either side 0 the said regenerative mass; means to effect a relative reciprocation between the o 11 compartments of the casing and the sand hoods, the latter being longitudinally divided into successive transverse compartments entirely open at the portion contiguous to the regenerative mass and having adjacent rows ofalternate openings and closures along the top and staggered relatively to each other;

and adjacentducts contiguous'tq. and conforming to the tops'jof the respective .hoods for supplying and removing air and gas thru the corresponding openings therein.

6. A regenerative preheater for air and the like in furnace. plants, comprising a casing divided transversely into a plurality of versely disposed and separated plates with intermediate separating and heat interchanging members; the latter affording a regenerative mass a pair of distributing hoods located respectively upon either side of the said regenerative mass; means to effect a relative reciprocation between the open compartments of the casing and the said hoods,

the latter being longitudinally divided into successive transverse compartments and entirely open at the portion contiguous to the regenerative mass and having adjacent rows of alternate openings and closures along the top and staggered relatively to each other, the free edges of the regenerator plates lying in surfaces generated by straight lines moving always parallel to the direction of reciprocation and the juxtaposed edges of the contiguous hood portions conforming thereto; and adjacent ducts contiguous to and conforming to the tops of the respective hoods for supplying and removing air and gas thru the corresponding openings therein.

7. A regeneratlve preheater for air and the like in furnace plants, comprising a casing divided transversely into a plurality of open compartments, and a regenerative mass of heat interchanging members located within said compartments; a pair of distributing hoods located respectively upon either side of the said regenerative mass, means to reciprocate said hoods lon itudinally thereof and in unison, said hoo s being longitudinally divided into successive transverse compartmentsentirely open at the portion contiguous to the regenerative mass and having adjacent rows of alternate openings and closures along the top and staggered relatively to each other; and adjacent ducts contiguous to and conforming to the tops of the respective hoods for supplying and removing air and gas thru the corresponding openings therein.

In testimony whereof, I have hereunto i signed my name.

open compartments by a pluralityof trans- 110 OTTO 1m LORENZI. 

